SOLUTION: Blake is working his way through school. He works two part-time jobs for a total of 32 hours a week. Job A pays $6.10 per hour, and Job B pays $⁢7.20 per hour

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Blake is working his way through school. He works two part-time jobs for a total of 32 hours a week. Job A pays $6.10 per hour, and Job B pays $⁢7.20 per hour      Log On


   

Question 1104019: Blake is working his way through school. He works two part-time jobs for a total of
32
hours a week. Job A pays
$6.10
per hour, and Job B pays
$⁢7.20 per hour. How many hours did he work at each job the week that he made
$211.70
.
Answer by ikleyn(52770) About Me  (Show Source):
You can put this solution on YOUR website!
.
     x +      y = 32        (1)    (hours, counting Blake's working hours)
6.10*x + 7.20*y = 211.70    (2)    (dollars, counting his earnings)


Multiply eq(1) by 6.10 (both sides).  The modified (and equivalent) system is THIS:

6.10x +  6.10*y = 6.10*32   (3)
6.10*x + 7.20*y = 211.70    (4)


Now subtract eq(3) from eq(4) (both sides).  The terms "6.10*x" will cancel each other,
and you will get a single equation for only ONE unknown y   (it is how the Elimination method works)

7.20*y - 6.10*y = 211.70 - 6.10*32,

1.10y = 16.5  ====>  y = 16.5%2F1.10 = 15.


Answer.  Blake worked 15 hours for B and 32-15 = 17 hours for A.

Solved.

On the way, you learned on how the Elimination method works.